Usually computer-based document-search processors use keywords. The result of a keyword search is often an enormous amount of information, the majority of which is irrelevant to user's requirements.
The precision of a search can be increased, if the user formulates the query as a problem, for example, “produce aluminum layer”, or “heat water”, or “oxidize silicon wafer”. But such formulations severely decrease the quantity of found information because the search will not find expressions such as “form Al layer” that are similar to “produce aluminum layer”, or expressions such as “increase temperature of water” that are similar to “heat water”, or expressions such as “perform oxidation of silicon substrate” that are similar to “oxidize silicon wafer”.
It is possible to provide a complete and more exact search with help of a dictionary of search synonyms e.g. in the form of Al layer=produce aluminum layer . . . , etc. But estimates show that volume of entries in such a dictionary would be huge—more than 107 expressions to describe different problems in just technical fields. Expansion into other (nontechnical) disciplines will lead to multiple expansion of this dictionary (up to 1011 expressions).
An object of the invention is to improve search systems.